Treesearch

Laurel wilt is a destructive vascular disease of trees in the laurel family (Lauraceae) caused by a nonnative insect/pathogen complex. This study monitored the recent spread and impact of laurel wilt in sassafras (Sassafras albidum [Nutt.] Nees) from the Gulf-Atlantic Coastal Plain region of the southeastern United States (US) into the adjacent Piedmont/Sandhills and Mountain regions. Laurel wilt was detected at thirteen of forty-six sassafras sites including seven outside the Coastal Plain. Compared to nondiseased sites, sassafras mortality due to laurel wilt increased rapidly from 2018...

A predator, Laricobius osakensis Montgomery and Shiyake (Coleoptera: Derodontidae), is being mass-produced and released for the biological control of the invasive hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). To better understand and predict the seasonality of this predator in North America, the development and reproduction of L. osakensis were evaluated at constant temperatures ranging from 5 to 22°C. The predicted seasonal biology was compared with data from field collections. L. osakensis did not complete development from egg to adult at the two lowest...

The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae), is a major pine tree killer in North and Central America. In the southeastern USA, responses by D. frontalis to its aggregation pheromone can be substantially increased by at least three host odours: the monoterpenes alpha-and beta-pinene, and the phenylpropanoid 4-allylanisole. We executed three trapping experiments to assess the influence of 4-allylanisole release rate on aggregation behaviour of D. frontalis and to evaluate the compound as an adjuvant for the operational monitoring lure...

Climate change is altering the geographic distribution of many species, including numerous forest insect pests, with the potential for severe impacts to forest ecosystems. The southern pine beetle (Dendroctonus frontalis), one of the world’s most persistently destructive forest pests, has extended its distribution towards the north, while impacts within its historic range in the southeastern United States have diminished, indicating that a range shift may be occurring. This pattern could be explained by the hypothesis of climatic envelopes if summers in the southern part of the range are...

Aggressive bark beetles colonize and kill healthy conifers through pheromone-mediated mass aggregation. In several species, the focal point of aggregation moves progressively from mass-attacked ‘focus trees’ to adjacent, unattacked ‘recipient trees’, resulting in infestation growth. This process, termed ‘switching’, is hypothesized to be mediated in whole or in part by antiaggregation pheromones released by beetles as colonization intensifies on a focus tree. We tested this hypothesis with the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae),...

Changes in global bioenergy consumption have catalyzed the emergence of forest plantations as an important energy alternative. In the southeastern United States, land cover changes caused by increasing demands for pine trees as a bioenergy feedstock incite associated impacts on local ecosystem services (e.g., water yield). However, water yield impacts from pine plantation management strategies, such as thinning and short rotation, have yet to be simultaneously examined on multiple spatial scales. Here, we modeled the effects of thinning and clear-cut conditions on long term mean annual...

The varied and wide-reaching impacts of climate change are occurring across heterogeneous landscapes characterized by a broad diversity of soil types. Despite the known importance of soils in mediating biogeochemical nutrient cycling, there is little experimental evidence of how soil characteristics may shape aqueous nutrient losses from forest ecosystems under climate change. Our objective was to clarify how soil characteristics modify the impact of climate changes on carbon and nutrient leaching losses in temperate forests. We therefore conducted a field-based mesocosm experiment with...

Public participation processes influencing National Forest management in the United States have shifted significantly because of the global COVID-19 pandemic. Although the United States Forest Service has used virtual participation tools in the past to support participation, the pandemic was the first time staff had to solely rely on such methods. Using the Trinity of Voice theory concepts of access, standing, and influence, we discuss how each has been and can be impacted by virtual vs. in- person public participation in federal land governance. Lessons are drawn from two peer-to-peer...

Climate classification allows an efficient encapsulation of climate data into climate units. For North America and most of Central America during 20, 14, 13, 11, 10, 7, 5, and 1 thousand years ago (ka) and recent years, I applied a Köppen-Trewartha classification system, but with dry classes subsumed under primary thermal classes to preserve information. The boreal and polar classes decreased from a combined 70% of area during 20 ka until reaching 42% of area at 7 ka, after which the area remained relatively stable. Conversely, the subtropical and temperate classes increased from 25% of...

For over two decades, Forest Stewardship Council (FSC) certification for community forestry has occurred in tropical countries. However, community forests represent just over 1% of the total FSC-certified forest area worldwide. Certification can promote more socially and environmentally responsible forest management while delivering economic returns to communities, but communities face challenges to obtaining, maintaining, and benefiting from it. Our analysis of the published literature finds that community forestry certification delivers many social and environmental benefits, often more...